Quickest here:STL 1:35.212 Danny Steyn, Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta race · FX 1:25.399 Trent Walko, Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta race
STLFXsolid race · dashed qualifying · slower is lower
STLFXsolid race · dashed qualifying · each class's best lap as a share of STL's at the same event (the reference class, changeable above); 100% is level, higher is quicker
Event
STL
FX
Qual best
Race best
Trap
Qual best
Race best
Trap
vs STL
% of STL
Atlanta Region SCCA Hoosier Super Tour @ Michelin Raceway Road Atlanta ST26MAR062026-03-06
1:37.000Danny Steyn · fastest of 15 · top 5 within 1.6s+0.012s (+0.01%)
1:36.825Danny Steyn · fastest of 14 · top 5 within 3.2s-0.382s (-0.39%)
126.5Derek Ketchie+6.5 mph (+5.4%)
3 rule changes (STL: 3)2 weight · 1 wording · STL minimum weights increase across all classes, 1300 cc gains 195 lbs to 1950, up to 1850 cc at 2500. · STL/STU Lotus weight reduced: Evora GT4 to 2700 lbs, Elise Cup R to 2250 lbs, Elise/Exige SC to 2450-2550 lbs. · STL Mazda MX5 Challenge minimum weight now references GCR 9.1.7.1 instead of 2500 lbs; spec components removed, only alternative tires allowed.showhide
STL Weight adjustment for STL #39579weightslowerSTL minimum weights increase across all classes, 1300 cc gains 195 lbs to 1950, up to 1850 cc at 2500.
STL Lotus Weight Reduction #38772weight -50 lbsfasterSTL/STU Lotus weight reduced: Evora GT4 to 2700 lbs, Elise Cup R to 2250 lbs, Elise/Exige SC to 2450-2550 lbs.
STL E&O: SMX Allowance in STL #37945wordingunclearSTL Mazda MX5 Challenge minimum weight now references GCR 9.1.7.1 instead of 2500 lbs; spec components removed, only alternative tires allowed.
Atlanta Region SCCA Hoosier Super Tour @ Michelin Raceway Road Atlanta ST25MAR072025-03-07
1:36.988Mike Taylor · fastest of 13 · top 5 within 2.0s+0.632s (+0.66%)
1:37.207Mike Taylor · fastest of 11 · top 5 within 1.3s+0.354s (+0.37%)
120.1Derek Ketchie+1.7 mph (+1.5%)
4 rule changes (STL: 1, FX: 3)2 weight · 1 cars added · 1 wording · FX Ligier JS F422 loses 15 lbs, to 1360 minimum weight. · STL/STU: 90-05 Mazda Miata alternate front wheel hubs moved from General to specific part approval. · FX Ligier JS F4 1st Gen minimum weight drops to 1405 lbs; 2nd Gen rises to 1375 lbs. · FX adds 2nd Gen Ligier JS F422 classification effective 2024-04-01.showhide
FX Request to Change to Weight for Ligier JS F422 #37124weight -15 lbsfasterFX Ligier JS F422 loses 15 lbs, to 1360 minimum weight.
STL Request to Remove Miata Hubs from General category #37138wordingwordingSTL/STU: 90-05 Mazda Miata alternate front wheel hubs moved from General to specific part approval.
FX Adjust minimum weights to align with pro F4 rules #36221weight -15 lbsfasterFX Ligier JS F4 1st Gen minimum weight drops to 1405 lbs; 2nd Gen rises to 1375 lbs.
FX Add Classification for 2nd Gen Ligier JS F422 #35844cars addedcars addedFX adds 2nd Gen Ligier JS F422 classification effective 2024-04-01.
Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta ST24MAR082024-03-08
1:36.356Danny Steyn · fastest of 15 · top 5 within 3.3s-0.113s (-0.12%)
1:36.853Danny Steyn · fastest of 17 · top 5 within 2.8s+1.641s (+1.72%)
118.3Mike Taylor-8.8 mph (-6.9%)
1:34.337Brad Yake · only car+5.991s (+6.78%)
1:36.351Brad Yake · only car+10.952s (+12.82%)
117.3Brad Yake-19.8 mph (-14.4%)
-0.502squal -2.019s
99.5%qual 97.9%
8 rule changes (STL: 5, FX: 3)2 induction · 1 cars added · 1 engine · 4 wording · FX Formula 4 now complies with Table 1 notes only; removed reference to FIA 2015 technical regulations and FIA/SCCA safety requirements. · STL and STU power steering rules clarified to permit electric-assisted and hydraulic-assisted steering systems. · STL Acura/Honda B-series and Mazda MZR restrictors reduced 2mm; minimum weights down 25–75 lbs for 1900–2000cc engines. · STL Mazda 12A must keep 5th and 6th intake port actuators and valves, no longer allowed removal or disabling. · STL Mazda RX-7 12A (79-85) now allows auto-type 2 bbl with 42mm choke(s) on dual-y manifold as alternate to stock Nikki 4 bbl. · Unable to summarize: FX Formula Mazda spec changes reference attached document not provided. · USF2000 Van Diemen with Mazda MZR LF-DE 2.0L added as spec line car in FC; removed from FX. · STL ITA/ITS RX7 and 1985+ ITA/ITS/ITB/ITC vehicles clarified to conform to section 9.1.4.2 tire specifications.showhide
FX Clarify Formula 4 Rules in FX #35700wordingunclearFX Formula 4 now complies with Table 1 notes only; removed reference to FIA 2015 technical regulations and FIA/SCCA safety requirements.
STL ST Electric-Assisted Steering Systems #35066wordingwordingSTL and STU power steering rules clarified to permit electric-assisted and hydraulic-assisted steering systems.
STL BOP Adjustments #35112inductionfasterSTL Acura/Honda B-series and Mazda MZR restrictors reduced 2mm; minimum weights down 25–75 lbs for 1900–2000cc engines.
STL Mazda 12A #35320engineslowerSTL Mazda 12A must keep 5th and 6th intake port actuators and valves, no longer allowed removal or disabling.
STL Alternate Carburetor Request for 79-85 RX7 12a #35181inductionunclearSTL Mazda RX-7 12A (79-85) now allows auto-type 2 bbl with 42mm choke(s) on dual-y manifold as alternate to stock Nikki 4 bbl.
FX FM Rules Update #34841wordingunclearUnable to summarize: FX Formula Mazda spec changes reference attached document not provided.
FX USF2000 Van Diemen with Mazda MZR LF-DE 2.0L in FC #34329cars addedcars addedUSF2000 Van Diemen with Mazda MZR LF-DE 2.0L added as spec line car in FC; removed from FX.
STL Clarify STL table B - IT spec notes on Tires #34187wordingwordingSTL ITA/ITS RX7 and 1985+ ITA/ITS/ITB/ITC vehicles clarified to conform to section 9.1.4.2 tire specifications.
Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta ST23MAR102023-03-10
1:36.469Danny Steyn · fastest of 16 · top 5 within 3.9s+0.493s (+0.51%)
1:35.212Danny Steyn · fastest of 17 · top 5 within 3.8s-0.267s (-0.28%)
127.1Mike Taylor+0.7 mph (+0.6%)
8 rule changes (STL: 1, FX: 7)2 engine · 1 cars added · 1 induction · 1 weight · 3 wording · FX: Wording clarified to remove references to FB and FM in GCR section 1.4.2.D. · STL Spec MX5 clutch, wheels, and tyres specified: ACT 0000-02-5004-G6, 17x8 wheels, Toyo RR and RA1 235-40-17. · Formula Renault 2.0 (10-17) reclassified from FX to FA; weight reduced to 1280 lbs, restrictor removed. · Pro Formula F2000 tube frame reduced to 4 forward gears, sequential carries 25 lb. weight penalty. · FX Formula Mazda minimum weight exception set to 1270 lb. · FX Formula Mazda engine spec changed to six-port 13B only; weight now per notes instead of 1350/1400. · Formula Renault 2.0 (10-17) now requires 45mm Flat Plate Intake Restrictor; fairings prohibited before or after. · USF2000 Tube Frame may now use Performance Electronics PE3-8400 ECU as alternative to Pectel T2.showhide
FX E&O - Remove references to FB and FM in GCR section 1.4.2.D #33725wordingwordingFX: Wording clarified to remove references to FB and FM in GCR section 1.4.2.D.
STL Spec MX5 in STL #33473wordingwordingSTL Spec MX5 clutch, wheels, and tyres specified: ACT 0000-02-5004-G6, 17x8 wheels, Toyo RR and RA1 235-40-17.
FX Reclassify 2010-2017 Formula Renault 2.0 as a spec line car in FA #33395cars addedfasterFormula Renault 2.0 (10-17) reclassified from FX to FA; weight reduced to 1280 lbs, restrictor removed.
FX Pro Formula F2000/USF2000 Transmission E&O #32823engineslowerPro Formula F2000 tube frame reduced to 4 forward gears, sequential carries 25 lb. weight penalty.
FX Formula Mazda Minimum Weight #33010weightslowerFX Formula Mazda minimum weight exception set to 1270 lb.
FX Formula Mazda Spec Line E&O Corrections #33011engineunclearFX Formula Mazda engine spec changed to six-port 13B only; weight now per notes instead of 1350/1400.
FX Formula Renault 2.0 (10-17) Intake Restrictor #32745inductionslowerFormula Renault 2.0 (10-17) now requires 45mm Flat Plate Intake Restrictor; fairings prohibited before or after.
FX Allow Performance Electronics PE3-8400 for USF2000 MZR #32767wordingwordingUSF2000 Tube Frame may now use Performance Electronics PE3-8400 ECU as alternative to Pectel T2.
Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta ST22MAR122022-03-12
1:35.976Danny Steyn · fastest of 18 · top 5 within 2.9s-0.449s (-0.47%)
1:35.479Danny Steyn · fastest of 18 · top 5 within 3.2s-1.326s (-1.37%)
126.3Trever Degioanni+2.5 mph (+2.1%)
1:28.346Trent Walko · fastest of 4 · top 4 within 6.6s+0.215s (+0.24%)
1:25.399Trent Walko · fastest of 4 · top 4 within 5.7s-2.391s (-2.72%)
137.1Trent Walko+2.7 mph (+2.0%)
-10.080squal -7.630s
89.4%qual 92.1%
18 rule changes (STL: 11, FX: 7)5 tyres & wheels · 2 cars added · 2 induction · 1 engine · 1 weight · 6 wording · 1 other · STU normally aspirated engines: minimum weights reduced up to 310 lbs; single throttle body weight reduction removed. · STL and STU Improved Touring vehicles must conform to 9.1.4 Tires & Wheels requirements. · Formula Mazda tire marking no longer required; compliance now referenced to updated online specifications document. · FX Formula 4 tire choice becomes unrestricted; must comply with FIA F4 2015 Technical Regulations and subsequent safety requirements. · FX USF2000 Tube Frame front tyre changes from radial to unspecified type, rear tyre options added. · FX Formula Renault 2.0 (00-17) tire choice unrestricted; original components required except repairs. · STL and STU piston engines clarified: intake manifold and cylinder head porting remains free. · STL Mazda Renesis flat plate restrictor increases from 55mm to 60mm. · STL Mazda RX-7 12A 79-85 clarifies carburetor, emissions, and water jacket modification rules. · STL Spec MX-5 removes redundant specification line; no performance change. · FX USF2000 Tube Frame allows Hoosier radials 20.5x7.0x13 front and 22.5x8.0x13 rear, FC-compliant shocks, Wilwood brakes, Bosch spark plugs. · FX USF2000 Tube Frame now allows any Hoosier radial tire 20.5x7.0x13 front, 22.5x8.0x13 rear. · STL Volkswagen 2.0L TFSI 1984cc classified with turbocharger removal required, meeting all other STL specs. · FX adds 2000-2009 Formula Renault 2.0 / Fran-Am 2000 classified at 1250 lbs with sealed 2.0L Renault F4R 832 engine. · STL Pontiac Solstice/Saturn Sky allowed 4" ride height. · STL Mazda B5 DOHC added to classification with standard STL regulations. · STL Honda B16A JDM restrictor reduced from 54mm to 53mm. · ST oil coolers and filters now explicitly allowed to be added or substituted; wording clarifies existing permissions.showhide
STL Single TB Weight Modifiers #31449weightfasterSTU normally aspirated engines: minimum weights reduced up to 310 lbs; single throttle body weight reduction removed.
STL Improved Touring Tires #32063tyres & wheelstyres & wheelsSTL and STU Improved Touring vehicles must conform to 9.1.4 Tires & Wheels requirements.
FX FM Rule Set Clarification #31881wordingwordingFormula Mazda tire marking no longer required; compliance now referenced to updated online specifications document.
FX E&O F4 Tires #31940tyres & wheelsfasterFX Formula 4 tire choice becomes unrestricted; must comply with FIA F4 2015 Technical Regulations and subsequent safety requirements.
FX E&O USF2000 Tube Frame #31951tyres & wheelsunclearFX USF2000 Tube Frame front tyre changes from radial to unspecified type, rear tyre options added.
FX URGENT - FX- Formula Renault Tire #32058tyres & wheelsfasterFX Formula Renault 2.0 (00-17) tire choice unrestricted; original components required except repairs.
STL Throttling Device Clarification #31323wordingwordingSTL and STU piston engines clarified: intake manifold and cylinder head porting remains free.
STL Mazda Renesis Restriction #31467inductionfasterSTL Mazda Renesis flat plate restrictor increases from 55mm to 60mm.
STL Clarification of 79-85 RX7 Spec line #31621wordingwordingSTL Mazda RX-7 12A 79-85 clarifies carburetor, emissions, and water jacket modification rules.
STL Request to clean up Spec MX-5 Redundancy #31069wordingwordingSTL Spec MX-5 removes redundant specification line; no performance change.
FX Rules Adjustment #30950otherotherFX USF2000 Tube Frame allows Hoosier radials 20.5x7.0x13 front and 22.5x8.0x13 rear, FC-compliant shocks, Wilwood brakes, Bosch spark plugs.
FX FX/FRP Tire Rule #30723tyres & wheelstyres & wheelsFX USF2000 Tube Frame now allows any Hoosier radial tire 20.5x7.0x13 front, 22.5x8.0x13 rear.
STL VW Engine Request #30625engineslowerSTL Volkswagen 2.0L TFSI 1984cc classified with turbocharger removal required, meeting all other STL specs.
FX Classify the 2000-2009 Formula Renault 2.0 / Fran-Am 2000 #30460cars addedcars addedFX adds 2000-2009 Formula Renault 2.0 / Fran-Am 2000 classified at 1250 lbs with sealed 2.0L Renault F4R 832 engine.
STL Request Mazda B5 DOHC #30420cars addedcars addedSTL Mazda B5 DOHC added to classification with standard STL regulations.
STL Honda B16A (JDM) Restrictor change #30531inductionslowerSTL Honda B16A JDM restrictor reduced from 54mm to 53mm.
STL ST Oil Coolers E&O Correction to 9.1.4.2.H #30388wordingwordingST oil coolers and filters now explicitly allowed to be added or substituted; wording clarifies existing permissions.
Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta ST21MAR192021-03-19
1:36.425Danny Steyn · fastest of 24 · top 5 within 3.0s
1:36.805Danny Steyn · fastest of 22 · top 5 within 3.1s
123.8Eric Diaz
1:28.131Austin Hill · fastest of 6 · top 5 within 3.8s
1:27.790Austin Hill · fastest of 6 · top 5 within 4.1s
134.4Austin Hill
-9.015squal -8.294s
90.7%qual 91.4%
39 earlier rule changes on record, in force before Atlanta Region Hoosier SCCA Super Tour @ Michelin Raceway Road Atlanta (from 2019)9 cars added · 8 induction · 3 weight · 2 aero · 2 engine · 15 wording · STL GM Ecotec engines now permit any combination within the family, must use 55mm flat plate restrictor. · STL/STU 90-05 Mazda Miata gains approval for Mazda Motorsports Development alternate front wheel hubs. · ST cars may relocate ABS actuation hardware and wiring anywhere in engine compartment. · STL rear wing trailing edge, including end plates and gurney flap, maximum rearward mounting clarified to center of rearmost bodywork. · STL allows OEM gear sets from same manufacturer transmissions with input shaft modifications for fitment. · Formula Renault 2.0 (2010–2017) newly classified in FX, must comply with Table 1 notes. · STL RWD strut suspension weight penalty cut to 0.5%, other RWD cut to 2.5%. · STL Honda F20C loses 2% weight penalty, minimum weight reduced by approximately 35 lbs. · STL Honda B16/B17/B18C1 restrictor tightened to 53mm; B18C variants and Mazda MZR to 52mm. · FX FormulaSPEED FS2.0 specification requirements updated; World Speed Inc. deadline removed, compliance now per SCCA website. · ST aero devices and reference areas now include end plates but exclude fasteners protruding over 1/2 inch. · Formula Ireland / Formula FX added to FX classification under Table 1 with compliance notes. · STL and STU clarify weight adjustment calculation order: engine adjustments first, then chassis adjustments. · STL and STU rear wing rules clarify that wicker is a Gurney flap; no performance change. · Formula Ireland/Formula FX car addition to FX Table 1 pending specification submission; not recommended. · GT3 and STU add Borg-Warner EFR6258 to approved turbocharger list. · STL adds 2016-2019 Mazda MX-5 Global Cup at 2000cc, 2450-2550 lbs minimum weight. · STL Mazda MX-5 Club Model 06-15 allows Mazda header part number 0000-06-5407-NC. · STL Honda/Acura B18 non-C gets 54mm restrictor; B18C variants drop B18C1, get 53mm restrictor. · STL Honda B18 restrictor reduced from 54mm to 53mm flat plate; B18C1 added with 54mm restrictor. · Ex-Pro Formula Super Vee classified in FX with 1190 lbs minimum weight, 1600cc or 1835cc VW engine, 6in front and 8in rear wheels. · FormulaSPEED reclassified from FA to FX with 2.0L Mazda MZR engine, 1350 lbs minimum weight, sealed ECU and dampers. · STU GM Ecotech LNF now allowed with turbo removed or with LE5 head and intake manifold, meeting STL specs. · STL Mazda MZR restrictor reduced from 54 mm to 53 mm. · STL Mazda MZR restrictor reduced from 55 mm to 53 mm. · FX Formula Mazda no longer requires tire marking; must comply with December 2019 GCR rules. · STL Mazda Spec MX5 Challenge adds approved wheel part numbers 0000-04-5706-GM, 0000-04-5706-SL. · Pro Formula F 2000 Tube Frame engine now must follow current FC rules with restricted ECU map, cams, and air restrictor required. · Mazda Spec MX-5 Challenge classified in STL with 2000cc displacement and 2500 lbs minimum weight. · STU alternate intake manifolds now allowed case-by-case instead of prohibited. · STL Acura/Honda B18 except C engine restrictor increases from 53mm to 54mm flat plate. · STL and STU ride height measurement clarified: without driver, at rocker panel lowest point, excluding pinch weld. · STL adds VW 1.8L R4 20VT 1781cc, 1 minimum weight, turbo removed permitted. · STL Mazda Renesis minimum weight reduced from 2800 to 2700 lbs. · STL Mazda MX-5 Cup brake pad compound changed to open. · STL adds Acura/Honda B18C1 GSR with 54mm flat plate restrictor and port matching limited to 1 inch. · STL Mazda 12 and 13B now permit port matching; previous ban removed. · STL B18C Type R variants get 54mm flat plate restrictor; B17 also gets 54mm restrictor. · STL Mazda Miata removes maximum displacement limit and adjusts minimum weight.showhide
STL GM Ecotec engines in STL #30247wordingwordingSTL GM Ecotec engines now permit any combination within the family, must use 55mm flat plate restrictor.
STL Super Touring Alternate Miata Hubs #30345wordingwordingSTL/STU 90-05 Mazda Miata gains approval for Mazda Motorsports Development alternate front wheel hubs.
STL Brake Component Relocation #29990wordingwordingST cars may relocate ABS actuation hardware and wiring anywhere in engine compartment.
STL Super Touring Wing Clarification #30111aeroaeroSTL rear wing trailing edge, including end plates and gurney flap, maximum rearward mounting clarified to center of rearmost bodywork.
STL Transmission Options #30118wordingwordingSTL allows OEM gear sets from same manufacturer transmissions with input shaft modifications for fitment.
FX Request for Car Classification to Compete in Formula X #29933cars addedcars addedFormula Renault 2.0 (2010–2017) newly classified in FX, must comply with Table 1 notes.
STL Request for FWD and RWD Parity #29728weightfasterSTL RWD strut suspension weight penalty cut to 0.5%, other RWD cut to 2.5%.
STL Request to Remove Honda F20C 2% Weight Penalty #29815weightfasterSTL Honda F20C loses 2% weight penalty, minimum weight reduced by approximately 35 lbs.
STL Request for FWD and RWD Parity #30023inductionslowerSTL Honda B16/B17/B18C1 restrictor tightened to 53mm; B18C variants and Mazda MZR to 52mm.
FX Update specifications for FormulaSPEED cars #29674wordingwordingFX FormulaSPEED FS2.0 specification requirements updated; World Speed Inc. deadline removed, compliance now per SCCA website.
STL Request clarification on wing measurement #29640aeroaeroST aero devices and reference areas now include end plates but exclude fasteners protruding over 1/2 inch.
FX Follow up to to Letter#28991 Request for FX classification #29281cars addedcars addedFormula Ireland / Formula FX added to FX classification under Table 1 with compliance notes.
STL Minimum Weight Determination #27695wordingwordingSTL and STU clarify weight adjustment calculation order: engine adjustments first, then chassis adjustments.
STL ST Gurney flap Wicker clarification #29012wordingwordingSTL and STU rear wing rules clarify that wicker is a Gurney flap; no performance change.
FX Request to be added to FX group #28991cars addedcars addedFormula Ireland/Formula FX car addition to FX Table 1 pending specification submission; not recommended.
STL Request for Addition to GT3 Approved Turbo List #27576wordingwordingGT3 and STU add Borg-Warner EFR6258 to approved turbocharger list.
STL Request to add 2016-2019 GMX-5 Spec line #28604cars addedcars addedSTL adds 2016-2019 Mazda MX-5 Global Cup at 2000cc, 2450-2550 lbs minimum weight.
STL Request to update PN for MX-5 #28622wordingunclearSTL Mazda MX-5 Club Model 06-15 allows Mazda header part number 0000-06-5407-NC.
STL Correction - Clarification Honda/Acura B18B engine Letter # 26209 #28873inductionunclearSTL Honda/Acura B18 non-C gets 54mm restrictor; B18C variants drop B18C1, get 53mm restrictor.
STL STL Honda B18 restrictor changes #28794inductionfasterSTL Honda B18 restrictor reduced from 54mm to 53mm flat plate; B18C1 added with 54mm restrictor.
FX Request to classify FSV in FX #28057cars addedcars addedEx-Pro Formula Super Vee classified in FX with 1190 lbs minimum weight, 1600cc or 1835cc VW engine, 6in front and 8in rear wheels.
FX Classify FormulaSPEED in FX #28715cars addedcars addedFormulaSPEED reclassified from FA to FX with 2.0L Mazda MZR engine, 1350 lbs minimum weight, sealed ECU and dampers.
STL Change GM LNF 2.0 Allowance to LSJ Engine for Viable STL 2.0 #27884engineslowerSTU GM Ecotech LNF now allowed with turbo removed or with LE5 head and intake manifold, meeting STL specs.
STL Acura/Honda B18C engine chart. Reduce the current 54 mm flat plat #28663inductionslowerSTL Mazda MZR restrictor reduced from 54 mm to 53 mm.
STL Mazda MZR engine chart. Reduce the current 55 mm flat plate to 53 #28664inductionslowerSTL Mazda MZR restrictor reduced from 55 mm to 53 mm.
FX Request to remove tire marking language from FM #28415wordingwordingFX Formula Mazda no longer requires tire marking; must comply with December 2019 GCR rules.
STL Request to add wheel part numbers #28342wordingwordingSTL Mazda Spec MX5 Challenge adds approved wheel part numbers 0000-04-5706-GM, 0000-04-5706-SL.
FX Change to FX Table 1 #28322engineslowerPro Formula F 2000 Tube Frame engine now must follow current FC rules with restricted ECU map, cams, and air restrictor required.
STL Request to Classify Spec MX-5 Challenge in STL #27399cars addedcars addedMazda Spec MX-5 Challenge classified in STL with 2000cc displacement and 2500 lbs minimum weight.
STL Request clarification for manifold and throttle in STU #27004inductionfasterSTU alternate intake manifolds now allowed case-by-case instead of prohibited.
STL Request Restrictor Plate correction #26779inductionfasterSTL Acura/Honda B18 except C engine restrictor increases from 53mm to 54mm flat plate.
STL Request Ride Height Clarification #26597wordingwordingSTL and STU ride height measurement clarified: without driver, at rocker panel lowest point, excluding pinch weld.
STL Request to reduce weight of RX8 with Renesis rotary #25781weight -100 lbsfasterSTL Mazda Renesis minimum weight reduced from 2800 to 2700 lbs.
STL Request for Open Brake Pads On Mazda MX-5 Cup NC #25821wordingwordingSTL Mazda MX-5 Cup brake pad compound changed to open.
STL Request to clarify B18C1 GSR Honda B motor table #26209cars addedcars addedSTL adds Acura/Honda B18C1 GSR with 54mm flat plate restrictor and port matching limited to 1 inch.
STL Port Matching #26415wordingfasterSTL Mazda 12 and 13B now permit port matching; previous ban removed.
STL Request to equalize FPR Reduction on all B-Series Vtec Engines #24746inductionslowerSTL B18C Type R variants get 54mm flat plate restrictor; B17 also gets 54mm restrictor.
STL Request E&O for Mazda Miata Spec Line #25955wordingunclearSTL Mazda Miata removes maximum displacement limit and adjusts minimum weight.
Best is the class's fastest lap in that event's qualifying or race sessions, with the driver who set it, how many cars set a time that session and how close the top five were; a best from fewer than three cars is greyed. With two or more classes, "vs" is the gap of each class's best to the first class's at the same event. "% of STL" is the class's best as a share of STL's best at the same event (100% is level, less is quicker): weather and track condition move every class together, so this compares across years where the raw times do not. It still breaks when STL's own field changes or one session was wet and another dry. Newest event first. The coloured figure under each value is the change from the previous event that has one (green is quicker, red slower). Whole laps only, so events with different sector layouts still compare. Weather and track condition are not accounted for.